Two block of masses 1 kg 2 are connected by a metal wire going over a smooth pulley. The breaking stress of metal is `40/(3pi) xx10^(6)Mm^(-2)` . What should be the minimum radius of wire used if it should not break?`(g=10ms^-2)`

Options

A. 0.5mm
B. 1mm
C. 1.5mm
D. 2mm

Answer

C

Explanation

Breaking strength (or) Breaking stress
`sigma=F/A = 40/(3pi) xx10^(6)N//m^(2)`
`(3xx10)/(pir^(2)) =40/(3pi) xx10^(6)`
`therefore r=1.5xx10^(-3)m = 1.5mm`